Researchers from 15 Sections, Laboratories, or Branches have used the Facility during the past year and 16 researchers have been newly trained to use one or more of the instruments. As every year, LIS staff have assisted Facility users to apply advanced microscopy techniques, to improve the quality of their images, to quantitate the images, and to prepare these images for publication. NIAMS publications which have benefited from such help and/or show images collected on our instruments are listed in the bibliography. LIS staff have also helped with evaluation of new instruments that Facility users are interested in. Among NIAMS investigators' publications which could not have been completed without microscopy work carried out in the Light Imaging Section, we want to highlight the following work: 1) Suzuki et al. (Science, 2014) have identified previously unsuspected differences in downstream activation of immune cell receptors in response to different affinity antigens. This substantial progress in the understanding of the immune response involved extensive microscopy using Total Internal Reflection Fluorescence (TIRF) microscopy. The TIRF instrument had been acquired especially to make such studies possible; 2) Canna et al. (2014, Nature Genetics) identified a new spontaneous mutation in the inflammasome component NLRC4, in a patient with recurring fever and inflammation, thereby suggesting new targets for therapy of autoinflammatory diseases. Microscopy done by Dr. Zaal in LIS was important for evidence that macrophages from the patient with the mutation did contain inflammasomes in conditions in which control subjects do not. 3) Publications expanding our knowledge of several NIAMS research target areas such as arthritis (Gabay et al, 2013; Layh-Schmitt et al., 2013); skin and hair development and diseases (Isaac et al., 2014; Kim et al., 2014); basic muscle organization (Oddoux et al., 2013) and muscle diseases (Spampanato et al., 2013; Feeney et al., 2014). Each instrument of the Facility has been put to good use. The still recent Leica Slidescanner 400SCN that collects scans of whole slides with histology samples or fluorescently labeled tissue slices has been used steadily. Storage memory has been increased to address the needs created by a fast growth in scan numbers. For histology samples the Slidescanner works in automated mode. It produces high quality images that can be visualized online through a large range of magnifications, a la Google map. The instrument is handled by LIS staff exclusively. More than 1300 slides have been scanned for users in 9 Laboratories/Branches outside of the Light Imaging Section. Occasionally we have helped colleagues in other IRPs by scanning their slides.